[gomarlins3]

That is a long story. No, you do not need the heat shields. I have run without the top one for over a year. I have since put it back on to help keep the under hood heat down this summer.

P.S. I hope you didn't remove the bolt closest to the firewall that holds the battery heat shield in place. If you did, screw it back in BEFORE you put the heatshield back in and slide the heat shield over it. The heat shield has a cut out so it will slide over the bolt. Once the heat shield is in place, put another bolt in to help hold the shield in place and then tighten the bolt closest to the firewall all the way down. A racheting box wrench works best, TRUST me, I have removed that thing four times and bought a set of racheting box wrenches just for that 1 bolt. It is SOOOOO much easier with that tool. They also come in handy when you take out your cat. You will see why when you go to put it back in.